Retractable landing gear



Aug. 18, 1936. G. M. BELLANCA RETRACTABLE LANDING GEAR 2 Sheets-SheetFiled NOV. 2,1 1953 Aug 18, 1936 G. M. BELLANCA 2,051,02

RETRACTABLE LANDING GEAR Filed Nov. 2, 1955 z'sheets-sheet 2 FMH?.

Patented Aug. 18, 1936 UNITED STATES kmirri-:Nr oFFicE ApplicationNovember 2, 1933,

1 Claim.

, This invention relates to improvements in airplane landing gear andmore particularly to an improved retractable landing gear. v

Many types of retractable landing gear have been proposed heretofore.These each present disadvantages. Such mechanisms are not alwayspositive in operation; in addition to this, prior of the structure ofthe float. This was invariably accompanied by an increase in theparasitic resistance.

An object of the present invention is to provide a novel type ofretractable landing gear.

Another object is to provide an improved amphibian plane.

A further object is to provide an improved type of landing gearcharacterized by a low parasitic resistance when in the retractedposition.

A still further object is to provide an improved type of float strutmounting.

With these and other equally important objects in view, the inventioncomprehends the concept of providing a rectractable Wheel assemblage foramphibians, the installation of which does not require a modication ofthe contour of the oat structure. The invention also includes theprovision of an improved strut arrangement specifically correlated withrespect to the landing gear to insure minimum resistance.

In order to clearly explain the underlying principles to those skilledin the art, a typical physical embodiment is illustrated in theaccompanying drawings in which:

Figure 1 is a side elevation of the improved airplane.

Fig. 2 is a front view of the device shown in Figure 1.

Fig. 3 is a top section taken along line 3 3 of Figure 2; and

Fig. 4 is an enlarged detail of a section of the oat, on line 4 4 ofFigure 1.

As shown in the drawings, the invention may be embodied in an airplanehaving a fuselage I, of any desired type, which fuselage includes anempennage structure designated generally by the numeral 2. The plane isprovided with a suitable power plant driving the tractor propeller 3.Suitably positioned Within the fuselage is a pilots cockpit Il.

While the plane may be of any desired type, the one chosen forillustration is of the low wing Serial No. 696,432

monoplane type, having the wing sections 6 suitably secured to a lowerportion of the fuselage. Such wings are provided with wing tip pontoonssuitably secured to the wing as by the struts 8 and guy wires 9. TheWings 6 may be suitably braced as by the flying wires I0 and the landingWires II. Additional tension bracing means such as incidence wires maybe employed.

In the preferred embodiment, the plane is of the amphibian type.Associated with the fuselage is the float structure I2. This may be ofany approved design with a rear step portion. If desired, the pontoonmay be provided with the tail skid I2.

In accordance with the major principle of the present invention, thefloat is secured to the fuselage by securing means, which though rigidand adequate, yet is characterized by a relatively low parasiticresistance. Considered more specically, the mounting for the floatcomprises a plurality of float struts I3 attached at one end to thefloat and at the other to the under side of the fuselage. As shown inFigure 3, the entire float mounting, that is to say, the struts I3 areenclosed with the stream line fairing Id. At the upper and lowerportions, the fairing is faired into the fuselage and floatrespectively.

The fairing I4 serves not only to house the oat struts in the oneenclosure and thus diminish parasitic resistance, but it also serves asa housing member for the landing wheels, in a manner more fully to bedescribed.

The ground landing mechanism of the plane comprises the ground wheels I5with the axle of which is associated the oleo gear I6. The oleo gear isassociated with the frame I1, which as shown in Figures 1 and 3, maycomprise the angularly disposed sections I1 and I1. sections may bedetachable tegral piece and are pivoted upon the pivots I 8 positionedWithin the interior of the float. As

retraction of the landing gear involves a single pivotal movement and aplurality of differential movements or parallel linkages is avoided. Itwill likewise be appreciated, from an inspection of Figure 2, that theupper arm or portion of the frame I1 is deflected inwardly towardsthepoint of pivotal connection I8. This form of structure insures twoadvantages. it provides for a relatively wide space between the landingwheels when they are in the extended position and thus insuresoptimumstability of the plane when taXiing on Athe ground. When the landingwheels4v are retracted by a swing movement about the pivot I8, the upperportion of the frame I'I falls within the contour of the'fioat at theposition I1a (Figure 2). The vertical sectionoi the landing wheel frameoccupies the lvertical position I'Ib. In the retracted position,therefore, the wheel I5 and the associated vertical section of thelanding wheel frame occupies a yposition within the fairing I4..

It will be appreciated that the provision of the fairing I4 ispeculiarlyadvantageous. Not only does it serve to fair the float struts I3, but italso serves as a housing member for the `landing wheel I5, when thelatter is in position. rIhus, the necessary conformation of a housingfor the landing wheel is made not upon a iioat structure, but arelatively simple and inexpensive strut fairing. The advantages of thisin respect of installation cost and upkeep will immediately beappreciated. The only modifications of the typical float structurenecessitated by the present invention, is the provision of a smallindentation 2li (Figure 3) of a shape and depth only sufficient to housethe framing member Il. In view of the construction and movement of theframe member I1, it will be appreciated that such a change in the skinof the float structure can readily be made without'any sacrifice ofdesirable structurable float features.

The landing gear mechanism may be extended and retracted by any desiredtype of transmission mechanism.- .'Ihere is shown on the drawings, atypical mechanism for accomplishing this function, but this is givenmerely as illustrative of any mechanism which will subserve the desiredfunction. 'Ihis mechanism may comprise a crank or other suitable.operating member 2l positioned at an available point within the cockpit.Motion from the crank 2I may be transmitted to the landing gear throughthe sprocket 22, flexible drive 23, sprocket 24 and thence through theflexible drive 25 to the cross shaft 26. The cross shaft is securelymounted in suitable bearings within the interior of the oat and isprovided on each end of the worm 21. Meshingwith the wormz wheel 21 andkeyed upon the shaft I8, is the worm wheel 28. It will be understoodthat rotation of the crank 2| will cause a corresponding rotation of theworm wheel 28 through the intermediacy of the transmission mechanism andwill thus raise or lower the landing wheel structure. It will beunderstood that .as the landing gear is lowered to its fully extendedposition, the inner portion of the arm I9 engages a latch mechanism uponthe float, which latter may be locked through the operation of any`suitable locking means controlled from the cockpit. When it is desiredto retract the mechanism, the latch associated with the member I9 may beunlocked, after In the rst place, 1

the retracted which operation, the crank ZI will raise the landingmechanism to the position shown in Figure 2. Ogf course, it will beappreciated that the latch associated with the arm I9 may be unlocked bya preliminary movement of the cross shaft 276 and for this purpose, anytype of lost motion mechanism may be provided.

As will be seen from an inspection of Figure 1, the load water line A-Aextends below the position occupied by the pivots I8. Hence inembodyring the present invention in any float, no modification of thewater surface of the float is necessary. Furthermore, due to the factthat the bulky portions of the landing gear are housed within thefairing I4, and only a minor portion, i. e., the frame I'Ia, is housedwithin the float, but very slight modification of the float structure isnecessitated. It is also to be observed that when the plane is in theair, the fairing I4 serves the double function of fairing the struts I3and the bulky landing gear mechanism. The advantage of housing theWheels I5 within the fairing I4 rather rather than the oat, on the onehand, or the main wings of the plane on the other, will immediatelyrecommend itself to those skilled in the art.

It will be appreciated that the fairing I4 may be Imade of any suitablematerial of construction. Thus the fairing may be constructed of ratherthin plywood so as to serve only as a stream-line casing. If desired,however, stronger materials may be employed, such for example as lightweight high strength alloys, in which case the fairing may be utilizedto serve as a structural element. In these circumstances the casing I4then becomes a type of cabane strut, serving Yto transmit stressesbetween the float and the fuselage.

It will be appreciated that a very important advantageous result of thepresent invention is the possibility of utilizing a retractable landinggear mechanism upon a seaplane, without in any way modifying the wingstructure and with but a slight and simple modification of the skin orvhollow of the float.

While a preferred modification of the invention has been shown anddescribed, it will be understood that this is given merely to exemplifythe underlying principles of the present invention. The claims are,therefore, not to be considered limited to the particular embodimentselected for illustration except if such limitations are clearlyembodied by the appending claims.

What is claimed is:

In an amphibian plane having a fuselage, a float spaced below thefuselage, retractable landing wheels pivotally mounted within thecontour of the float; a plurality of struts interconnecting the fuselageand the float, a streamlined casing Y completely enclosing the strutsGIUSEPPE BELLANCA.

and being of approximately one-half the width of the float and

